Can't Trust Those Pesky Inspectors & Electicians
A couple years back, I was helping a friend settle into her brand new home. One of my tasks was replacing all of the toggle type wall switches with those "Decora" style paddle things.
Although the home had been inspected and signed off, we called the city and the electrical contractor back for some rework after I discovered loose wires on every switch I removed.
Most disturbing was that many switches in modern homes go to one section of each outlet in a room, so that you plug in floor lamps and operate them easily.
Downside is that people tend to plug other things -- like vacuum cleaners in.